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All the Fn + Key work except F5/F6 which control the screen brightness.

How can I get them to work?

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I have tried by updating the Kernel to the latest version. But I have found the best solution that can increase or decrease the brightness of the PC in Ubuntu using the function and brightness button. Just follow the steps:

Open terminal (Clt+Alt+T) and run the command given below:

sudo gedit /etc/default/grub

Now the new window opens and you will see the lines given below:



Now you have to change the lines above by the command lines given below:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force acpi_backlight=vendor"

Then save the window and Update the grub from the terminal using :

sudo update-grub

Now you can Increase or decrease the brightness of your PC in Ubuntu 12.04 and the other versions also. This technique can be used in HP DV6, Acer Aspire, Dell Inspiron, Toshiba and more others.

                    Hope this Helps!

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:< tried not working – Adrian Dec 7 '12 at 3:58

I have good news and bad news. After a routine 12.10 update installed kernal, F5 and F6 brightness keys work! The bad news is they only adjust about the top ten percent of the backlight brightness range.

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tried not working :< 12.10 – Adrian Dec 7 '12 at 3:57
True. And every other time, you can't adjust all the way down even with the help of xbacklight. So if you want to use laptop in darkness, you need to keep rebooting until it works... – Adam Ryczkowski Apr 4 '13 at 8:58

Have you tried Fn + up/down arrow keys, in case it's set up a "standard" keyboard?

Worth a quick try!


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they are bind as stop play forword backward fot N56VZ – Adrian Dec 7 '12 at 4:07

You can make all the function keys to work with Ubuntu 12.10. See my answer to a similar question.

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:< tried not working – Adrian Dec 7 '12 at 4:08

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